1. Field
The embodiments described herein relate generally to linear accelerators. More particularly, the described embodiments relate to modular linear accelerators for selective mounting onto various movable supports.
2. Description
A linear accelerator produces electrons or photons having particular energies. In one common application, a linear accelerator produces a radiation beam used for medical radiation treatment. The beam may be directed toward a target volume of a patient in order to destroy cells within the target volume by causing ionizations within the cells or other radiation-induced cell damage.
Conventional linear accelerators may be used for isocentric or non-isocentric radiation treatment. Isocentric treatment is typically delivered by a linear accelerator integrated into a rotatable gantry. The gantry rotates around a horizontal axis such that a beam emitted from the linear accelerator passes through a same volume of space (i.e., an isocenter) at each angle of rotation. A target volume of a patient is therefore positioned at the isocenter prior to emission of the beam and rotation of the gantry. Due to physical constraints, isocentric treatment is particularly suited to target volumes located above the chest region.
Multi-jointed robotic arms are typically used to deliver non-isocentric radiation treatment. Such arms include an integrated linear accelerator and may be precisely positioned with respect to a patient in order to deliver treatment radiation to a target volume located virtually anywhere within the patient. Non-isocentric radiation treatment therefore irradiates the target volume from fewer external positions than those used during isocentric radiation treatment.
Isocentric and non-isocentric radiation treatments present characteristic advantages and shortcomings. Treatment facilities would prefer to offer either or both types of treatment depending on the nature of a particular patient and patient volume. However, the purchase, maintenance, and staffing costs associated with an isocentric radiation treatment machine and with a non-isocentric radiation treatment machine often prevent facilities from offering both types of treatment. Even if costs were not prohibitive, the relative size of each type of machine typically prohibits co-location of two of such machines in a same treatment vault, thereby further exacerbating the current inefficiencies of offering both types of treatment.